High-potencial switch.



a. E. PALMER.

Patented Aug. 7, 1917.

3 SHEETSSHEET 1.

G. E. PALMER.

HIGH POTENTIAL SWITCH.

APPLICATION FILED FEB. L6, 1917.

1,236,537 9. Patented Aug. 7,1917.

3 SHEETS-SHEET 2.

E F Irzverzi'non- 6")?UlZhEh/lfigl' G. E. PALMER.

HFGH POTENTIAL SWITCH.

APPLICATION FILED FEB.16,l917.

1 ,236,379. Patented Aug. 7, 1917.

3 SHEETSSHEET 3.

- fnveuion Gr'anviZleEP nae mersed in a non-conducting UNITED STATES PATENT OFFICE.

. I GRANVILLE E. PALMER, OF BROOKLINE, MASSACHUSETTS, ASSIGNOR TO THE PALMER ELECTRIC & MANUFACTURING IOBATIQN' or MAINE.

COMPANY, 015 BOSTON, MASSACHUSETTS, A COR- HIGH'-POTENTIAL SWITCH.

Patented Aug. '7, 1917.

Application filed February 16, 1917. Serial No. 148,997.

To all whom it may concern:

Be it known that I, GRANVILLE-E. PAL- MER, a citizen of the United States, residing at Brookline, in the county of Suffolk and State of Massachusetts, have invented new and useful Improvements in High-Potential Switches, of which the following is a specification. i

This invention has relation to high potential switches, in which the contact members and thermal cutouts or fuses are immedium.

The object of the inventlon is to provide a switch of this general character having its parts so constructed and arranged that, when the contact members are in engagement and the fuse is in current-carrying position,\ access thereto is prevented, and that, When the contact members are separated and the fuse is exposed for inspection, removal or replacement, a barrier or shield is located to prevent access to the current carrying elements. A further object of the invention, is to so construct and arrange the elements or members of a switch of this general character that the arc resulting from the separation of the contact members Wlll be broken on a relatively short initial separating movement of such members; and another object of the invention is to insure the actual destruction, as a-current carrier, of the thermal cutout or fuse when the fusible metal reaches a molten condition due to a gradually increasing current, and thus prevent the fuse from continuing to carry "current, as is apt to be the case in fuses as now generally employed in actual practice. The invention has still further to provide certain novel features of construction and arrangement for securing certain desirable results or advantages, all as will be subse quently described herein.

While the invention is preferably embodied in a high potential switch in which the contact members and the fuses or thermal cutouts, when in operative position, are immersed in oil or like liquid insulating medium, I desire it to be understood at the outset that the presence of such liquid medium is not essential, and that they may be surrounded by airor other gaseous non-conducting medium.

The switch, which I have selected for illustration as containing an embodiment of my invention, is a high voltage oil switch suitable for use as a combination switch and thermal cutout, in which the circuit is broken in an effective manner by the contacts when used as a circuit breaker, and in which the thermal cutout or fuse stands in an effective position for proper operation in opening the circuit under conditions imposed by a gradually increased current overload.

The carrier for the fuses, of which certain portions thereof constitute the movable contact members of the switch, is constructed and arranged to move in a horizontal plane, in separating such members from the Sta tionary contact members and while immersed in the bath of oil so that the break is horizontal. This is a feature of value because the electric are produced between horizontally separating electrodes orcontact members, at a given potential in an insulating medium} such as either oil or air, is broken by a shorter separating movement of said members or electrodes than would pro duce a rupture if the movement were vertical or at a substantial inclination to the horizontal. Moreover, the value of two spaced horizontal breaks in the oil is that, if impurities exist in the oil such as would tend to maintain an arc, they tend to settle or collect in layers and strata, and, by the laws of probabilities, they would not occupy two vertically spaced zones, leaving at least one zone of clear oil in which the arc may be ruptured. In other words, if the lower pair of contact members is located in a stratum of are-maintaining carbon or other impurities, the other pair will be located in a higher stratum of pure oil in which there are no such impurities and the are formed therein will be quickly ruptured.

In accordance with the embodiment of the invention illustrated and hereinafter described, the fuses or thermal cutouts are arranged vertically, so that, when the fusible metal strip is gradually softened by an increasing current-overload, the molten condition therein first occurs at the upper part of ,the strip, allowing the unsupported lower half to drop or fall away and completely rupture the arc. The fuses are arranged upon a carrier which is movable horizontally about a vertical axis, and the ends of the fuses, which are arranged vertically, are moved by the carrier into and out of mechanical and electrical contact with stationary electrodes or contact members. When in their operative or current-carrying positions, the fuses are inaccessible beneath a plate or member, which, however, has openings with which the fuses register when they are in their inactive positions. When the carrier has been moved to place the fuses in their last-mentioned positions, the carrier may be moved vertically. to lift the fuses from the oil so that they may be removed from the carrier for inspection or renewal. There is in addition a cover or door which normally closes the openings in the plate referred to and which is locked in active positions at all times except when the fuses have been moved laterally to inactive position and have been lifted, and, when this has occurred, the cover may be moved to expose the openings. When the cover is in an in active position or is open, it looks the fuse carrier in the inactive position to which it had to be moved before the cover could be opened. The fuse carrier is provided with a barrier of insulating material, which, when the carrier is in inactive position, cuts oil' access to the live members or elements in the switch and prevents the operative from coming in contact therewith or from abstracting current therefrom. This barrier in the switch illustrated must be placed in its operative position before the cover or door can be opened.

In addition to these novel features of construction and arrangement by which the results referred to are achieved, there are .certain others which are illustrated and which I shall hereinafter describe.

Referring to the drawings,

Figure 1 represents in plan View a threepole high-potential switch embodying the invention, including 'the wall bracket or support therefor.

Fig. 2 represents a vertical section therethrough.

Fig. 3 represents a horizontal section on the line 33 of Fig. 2.

Fig. 4 is a diagram illustrating the circuits in the switch.

Figs. 5 and 6 respectively represent plan views'of the casing, and of the door or cover respectively.

' Referring now to the drawings,

10 indicates a wall bracket or wall support for the switch. It consists of an annulus having on one side what may be termed a base flange 11, through which screws may be passed into the wall of a building to support it in a horizontal position.

The switch casing 12 is cylindrical and is of such diameter that it may fit within the annular wall bracket, and it is provided on its exterior with projections 13 to rest upon the bracket. This construction enables the switch casing to be rotated about its vertical axis so as to adjust it to receive the conductors which may be brought to it from different directions. The cylmdrical'casing is formed or provided wlth a substantially fiat top or end wall which may be conveniently cast integrally therewith, although this is not essential since the top may be formed separately and secured thereto if desired. The bottom of the easing is closed by a lower end wall 15, circular in form and secured to the end of the cylindrical casing by screws 16, there being of course gaskets or packing rings 17 interposed between the parts. a The casing thus formed is capable of containing a body of oil, and this latter may be introduced through a T-fitting 18 which is screwed! into an aperture in the side of the casing near the top. A wing screw 181 may be threaded into either end of the fitting. In filling the casing with oil, the wing screw is threaded in the position shown in Fig. 2, so that, by means of a funnel, oil may be introduced through the fitting into the casing. When the level of the oil in the casing shows that a sufficient quantity has been introduced, the wing screw 181 may be removed and screwed into the upper end of the fitting so that the excess oil will flow out leaving the level in the casing at the height of the bore in the central portion of the fitting.

I will now describe the carrier by which the fuses or thermal cutoutsare moved into and out of active position. It consists of a plate 20 of somewhat the shape in plan view of a symmetrical three-leaf cam, as best shown in Fig. 3, and it is provided with three evenly spaced apertures 21, one in each of the leaves. These apertures are equally spaced from the center of the plate or carrier 20 and are designed to receive the fuses which may be placed vertically therein. The hub of the plate or carrier is cross pinned to a vertical spindle 22 which has a rotative and slide bearing in an annular boss 23 depending from the top or end wall of the casing. The reduced end of the spindle projects beyond the end wall and has cross pinned thereto a handle 24 by which it may be both rotated horizontally and moved vertically lengthwise under certain conditions as will be subsequently explained. Each fuse, of which there are three in the present case inasmuch as the switch is tripolar, is contained within a cylindrical shell 25 which is perforated to permit the inflow and outflow of the insulating medium. In a peripheral groove midway between the ends of the shell, there is sprung a s lit circular wire 26 which forms a circum erential bead or flange to rest upon the plate or carrier 20 and hold the fuse in position. The ends of the shell, which may be made of metallic tubing, are closed by heads 27 of suitable insulating material through which project the contact pieces or electrodes 28., Connecting these contact pieces or eletrodes is the fuse 29 which may consist of a strip of fusible metal or a group of fine wires,

or may otherwise be formed as best conforms to the existing practice. Encircling the fuse, there is a smaller cylindrical shell 30 of suitable nonconducting material which is preferably perforated to permit the entrance of the conducting medium. The apertures in the inner shell do not register with those in the .outer shell for the purunderstood by tion and that they may. be bodily. moved horizontally about a common axis, and, as will be subsequently explained, they may be moved vertically to a position to enable them to be removed from the interior of the casing.- The electrodes 28, which are prefer.- ably cylindrical in form and which project from the ends of the shells,- constitute the movable contact members of the switch, since they are moved into and out of engagement with the stationary members. There are, of course, three pairs of associated stationary contact members, one pair for each fuse. I will now describe how they are constructed and mounted. The contacts, with which may be engaged the upper electrodes of the fuses, are held between two. ring-like or annular members 32, 33, of suitable insulating material. The peripheral portions of these members are cylindrical but their internal walls are substantially the shape shown in dotted lines in Fig. 1. These ring-v like members 32, 33, are securedto an internal flange 34 projecting from the cylindrical Wall of the casing near the upper end thereof, screws 35 being passed upwardly through said members into the flange. In the lower plane there are two similar members 36, 37, so that, b an inspection of Fig. 3, the internal co guration of all four members 32, 33, 36 and 37 may be easily understood. The three pairs of stationary contact members or electrodes are arranged at equal distances about a common center, as shown in Fig. 3, and they may be of any approved. construction. The members of one pair are indicated at a a in Fig. 2, and it will be understood that there are similar electrodes at b b" and 0 0 as indicated in Figs. 1 and 3. Each contact member consists of a shank which is clamped between the contacting ring-like members, and at the radially inwardly projecting end of the shank there are attached two resilient clamps 38 between which the movable elec: trode 28 may enter and leave. The spring contact members 38, 38, are so arranged that, when the fuse carrier is moved in one direction, the fuse ends or electrodes 28 may be caused to engage them as shown in Fig. l; and, by moving the carrier clockwise, the fuses may be disengaged therefrom as will be readily understood. The ring-like members 36, 137, which are of course formed of insulating material, are arranged in parallelism with but below those at 32, 33, and are supported thereby by means of bolts 40, 41 42, 43 and 44, those at 40, 41, 42, being preferably of copper or other suitable conducting material, inasmuch as they serve as electrical conductors as will be explained. That portion of each bolt which lies between the adjacent faces of the ring-like members 33, 36, is covered and concealed within a tube 44 of non-conducting material.

The lower end of the bolt 41 is connected by a conductor 45 with the shank of the stationary electrode a, while the lower ends of the bolts 40, 42, are similarly connected by conductors 46, 47, with the shanks of the electrodes or stationary contact members I) c. are preferably between the two ring-like members 36, 37.

To the three bolts 40, 41

and 42 may be secured by any suitable means the terminals of the three incoming conductors which supply current to the stationary electrodes, and these conductors may be introduced through three apertures surrounded by annular bosses 48, 49 and 50 projecting upwardly from the top wall of the casing as shown in Figs. 1 and 2. Similarly the outgoing conductors may be passed through the apertures surrounded by the annular bosses 51, 52 and 53. It is immaterial how the electrical conductors are secured to the several bolts and to the stationary electrodes which are carried by the upper ringlike members 32, 33. It may sufiice to state that from-the stationary contact members or electrodes 1) and 0 there extend conductors 54, 55, to points immediately below the centers of the annular bosses 51, 53, and that they may be there engaged and held by screw-s similar to that indicated at 55 in Fig. 2. In this particular case, this screw is formed on or secured to the shank of the electrode a and it-serves as means to effect an electrical connection between said shank and the conductor 56. This conductor is covered with insulation as ordinarily, but the insulation is stripped from the end and the exposed wire is soldered or secured to an end piece 57 which is brought into engagement with the end of the screw 55 by a nut 58 connected by a bayonet joint or key with a sleeve 59. These parts, which have just been explained in detail, are not novel and serve merely as indicating one way of securing the six conductors which extend into the switch casing to the several elements to which they must be connected. In each case, the sleeve 59 is located within a projecting sleeve 60 of insulating material which may These last-mentioned conductors 46, 47

be cemented or otherwise rigidly secured within the annular boss through which it extends.

From this description, it will be apparent that there are three separate circuits through 'the switch, each including a pair of vertically separated stationary. contacts and a vertical movable fuse or thermal cutout adapted to be engaged therewith and disengaged therefrom. When the parts arein the position shown in Figs. 1 and 3, the current is carried from the incoming conductors to the outgoing conductors. By moving the switch carrier clockwise, the fuses and their electrodes will be disengaged from the stationary contacts. This disengaging movement of the fuse carrier will be through an arc of substantially 60, so that, when it reaches its end of movement, each fuse will be located at a point midway between two pairs of stationary contacts.

In order that the fuses may be removed from the carrier, the upper end wall or plate of thecasing is provided with three apertures 70, each large enough to permit the assage therethrough of one of the fuses.

hese apertures are located so as to be in alinement with the fuses when the have been moved to the inactive position ast referred to. I think it desirable, however, not only to move the fuses to their inactive position," but also to raise them so as to brin them close to the apertures through which they may be withdrawn. To this end, the spindle 22 is provided with a cross pin 71 which may be brought to register With two slots 72, 72, in the depending annular boss 23 when the fuse .carrier is in its inactive position, so that thereafter the entire fuse carrier may be raised vertically for a distance equal to the length of the slot so as to bring the fuses to points where they can be easily grasped by the fingers through the apertures and removed for inspection, repair. or replacement. The apertures 70,

however, are normally closed by a door or cover, and it'is only when the fuse carrier has been moved to inactive position and has been lifted, that this cover can be moved to expose the openings 70. The said cover consists of a circular plate 80 which rests upon the top of the end wall 14 and which is mounted to rotate on an annulus 81 projecting upwardly a short distance from the surface. of said end wall 14 and encirchrig the spindle 22. When the fuse carrier is raised, this cover plate may be rotated, but, when the fuse carrier is in its lowered position, said cover is held against movement by a pin82 which depends from a disk 83 mounted loosely on the reduced end of the spindle between the shoulder thereon and the handle 24. The pin 82 extends downwardly into a socket 85 formed in a lateral extension of the depending annular flange 23, and consequently, when the fuse carrier is in its operative position, the cover or door 80 is held a ainst movement without however preventing the rotation of the spindle 22 and the fuse carrier supported thereby. Assuming that the parts are in their active or operative positions, as shown in Fig. 2, an operator, by grasping the handle 24, may rotate the spindle and the fuse carrier clockwise to disengage the fuses from the stationary contacts and move them into inactive position. Thereafter the operator lifts the handle 24 to a point where the pin 82 is dislodged from its socket 85. The operator then, by grasping a small knob 86 on the cover plate, may rotate it so as to bring the apertures 87 therein into registration with the apertures 70, and, in so doing, an imperforate ortion of the plate slides under the end of the pin 82 so that the operator may release the handle 24 without its dropping. The operator now has access to the fuses. Before the fuse carrier can be restored to active position, it is necessary for the operator to partially rotate the plate 80 so as to allow the pin 82 to enter the socket 85, whereupon the handle can be lowered so as to immerse the fuse carrier and the fuses in the oil, after which the operator rotates the fuse carrier anticlockwise to bring the electrodes 28 into engagement with the stationary contacts or electrodes 38.

-I-have previously indicated that I provide barriers or obstructions which are interposed so as to prevent access to the current-carrying parts when the fuse carrier is in an inactive position. I have illustrated three of these barriers, each of which is indicated at 90. It consists of a curved sheet of insulatin material which is screwed or otherwise a xed to the peripheral portion of the fuse carrier and partially surrounds the adjacent fuse. Each barrier extends substantially lengthwise through the space between the ring-like members 33, 36, and effectively prevents an operator from reaching the current-carryin parts when the door 80 is open. Instead of aving three separate barriers 90, I might employ a single sheet which follows the curvature of the fuse carrier, as will be readily understood. a

It is quite apparent that, although I have described my invention in connection with a three-pole switch, it may be quite readily embodied in a double-pole switch and that the switch may be correspondingly simplified. It will of course be realized that the invention is not limited to the particular details of construction which I have illustrated and described in detail, since various equivalent parts or features may be utilized for those thus referred to.

In the diagram shown Fig. 4, A, B and C represent the incoming hne conducare laterally remote from the openings 70 in.

tors, and D, E and F the outgoing line conductors. Between these are located the fuses or thermal cutouts which are indicated generally at G, H and I.

From the foregoing description it will be seen that I have accomplished the objects referred to in the first part of this specification by means of simple elements which are the members 32, 33, 36 and 37 and their connecting bolts, which form a frame for the stationary contacts, are all assembled and attached together and the parts which are carried thereby are secured thereto before the frame is inserted in the casing. When the frame has been secured in place the several pairs of associated stationary contacts the top of the casing, as previously described. When the fuse carrier is moved horizontally about its axis, the barriers 9Q are placed or interposed between the openings and the live stationary contacts, to render the latter inaccessible. The vertical movement of the fuse carrier also raisesthe barriers close to the openings to still further guard against access to said current-carrying parts. It will doubtless be appreciated that, by the construction and mode of operation of the arts as herein illustrated and described, it is impossible to open the cover until the fuses have been brought to a state of rest at the end of their horizontal movements away from the stationary contacts, and until the barriers have been disposed in their active posit-ions effectively to prevent access to the stationary contacts or other live or currentcarrying parts;

One other point of advantage, due to the casing and its supporting bracket, is that the bracket may be installed in position before the casing and the switch are installed, and, of course, the casing and switch may be removed for any purpose without dislocating the bracket.

Having thus explained the nature of my said invention and described a way of making and using the same, although without attempting to set forth all of the forms in which it may be made or all of the modes of its use, what I claim is:

1. A switch comprising a casing, pairs of associated stationary contacts therein disposed in different vertical planes about a common center, an oscillatory carrier having a vertical axis coincident with said center and provided with pairs of movable contacts, means extendin from said casing for moving said carrier a out its axis, said casing havin one or more openings into registration with which said movable contacts may be brought, a cover normally covering such openings, and means by which said cover is lockedwhen the carrier is in opera-r, tive position and by which the carrier is locked in inactive position when the cover is open.

2. A switch comprising an oscillatory carrier movable about a vertical axis, one or more detachable fuses carried thereby, complemental stationary contacts disposed in different vertical planes and between which electrical connection may be made by such fuse or fuses, a casing inclosing said-carrier and said stationary contacts and having one or more openings for exposing said fuses when said carrier is in inactive position, means for oscillating said carriers to cause said fuse or fuses to register with said opening or openings, a cover for closing said opening or openings, and means for locking said cover closed when the carrier is in active position and for locking the carrier in inactive positionwhen the cover is open.

3. A switch comprising an oscillatory carrier movable about an axis, one or more detachable fuses carried thereby, stationary contacts dis osed about said axis between which electrical connection may be made by such fuse or fuses, a casing inclosing said carrier and said stationary contacts and having one or more openings for exposing said fuses when said carrier is in inactive position, means for oscillating said .carriers to cause said fuse or fuses to register with said. opening or openings, and for moving saidcarrier axially to bring said fuse or fuses into accessible position in respect of said opening or openings.

4. A switch comprising a carrier movable about an axis, detachable fuses carried thereby, pairs of stationary contacts disposed about said axis to be electrically connected by said fuses when the carrier is in active position, a casing inclosing said carrier and stationary contacts and having openings with which the fuses register when the carrier is in inactive position, and means accessible exteriorly of the casing for moving said carrier about its axis to cause the I accessible exteriorly of the casing for moving said carrier about its axis to cause the fuses to register with said openings and for moving said carrier axially to advance said fuses toward said openings, a cover normally closing said openings when the fuse carrier is in inactive position and has been axially moved toward said openings, means by which said cover is locked closed when the carrier is in active position and by which the cover when open locks the fuse carrier in its inactive advanced position.

6. A switch comprising a casing, a spindle extending into said casing, a handle on the outer end of said casing, a carrier on the inner end of said spindle, a bearing for said spindle in which it may both osclllate and move axially inwardly and outwardly, stationary contacts in said casing, movable complemental contacts on said carrier adapted on oscillatory movement of said carrier to be engaged with and disengaged from said stationary contacts, and means for preventing outward axial movement of said spindle and carrier when the carrier is in active position with the movable contacts engaged with the stationary contacts and for permitting such axial movement when" the carrier is in inactive position with the movable contacts disengaged from the complemental stationary contacts.

7 A switch comprising a casing, a spindle extending into said casing, a handle on the outer end of said casing, a carrier on the inner end of said spindle, a bearin for said spindle in which it may both oscillate and move axially inwardly and outwardly, Stationary contacts in said casing, movable complemental contacts 0 said carrier adapted on oscillatory n-)vement of said.

carrier to be engaged with and disengaged from said stationary contacts, means for preventing outward axial movement of said spindle and carrier when the carrier is in active position with the movable contacts engaged with the stationary contacts and for permitting such axial movement when the carrier is in inactive position with the movable contacts disengaged from the com-.

plemental stationary contacts, said' casing having an opening for exposing the interior thereof, a cover oscillatory about the spindle body of oil immersin thereby about said axis into and out of electrical contact with said stationary contacts.

9. A high potential oil switch comprising a casing adapted to contain a body of oil, a pair of associated stationary contacts in said casing arranged in different parallel horizontal planes, a carrier in said casing movable about a vertical axis, a vertically arranged fuse on said carrier movable thereby about said axis into and out of electrical contact with said stationary contacts, and means exterior, of said casing for oscillating said carrier about its axis.

10. A high potential oil switch comprising a casing adapted to contain a body of oil, a fuse carrier normally immersed in the body of oil and movable about a vertical axis, a plurality of fuses mounted on said carrier and movable horizontally thereby through the body of oil, pairs of associated stationary contacts in said casing, and means for oscillating said carrier to cause the fuses to electrically connect and disconnect the contacts of therespective pairs of stationary contacts.

11. A high potential oil switch comprising a casing adapted to contain a body of oil, a fuse carrier in said casing movable about a vertical axis, a plurality of vertical fuses on said carriers, there being within the casing and immersed in the oil -,two vertically spaced movable contacts for each fuse a plurality of vertically spaced associated stationary contacts disposed about the axis of said carrier and adapted to beengaged by the corresponding movable contacts of the respective fuses, and means for oscillating said carrier about its vertical axis.

12. A high potential oil switch comprising a fuse carrier movable about a vertical axis, a fuse thereon movable horizontally about said axis and having associated movable contacts, a pair of stationary contacts, a casing inclosing said carrier, said fuses and said contacts, and adapted to contain a said last-mentioned elements, said casing aving an o ening to ermit access to said fuse when t e carrier is in inactive position, a cover normally locked in position to close said opening when the carrier and fuse are in active position, and means for moving said carrier about its vertical axis to active and inactive positions respectively.

13. A high potential oil switch comprisin a fuse carrier movable about a vertical axls, a vertically arranged fuse thereon having associated vertically-spaced movable contacts, a pair of associated verticallyspaced stationary contacts, a casing inclosing said carrier, said fuse and said contacts, and adapted to contain oil in which said parts are immersed, means for oscillating said carrier about said axis, said casing having in its top an opening to expose said fuse when the carrier has been oscillated to inactive position, a cover normally closing said opening, means for locking said cover in closed position whenthe carrier is in inactive position, and means by which the carrier is locked in inactive position when the cover is open.

14. A high potential oil switch comprising a fuse carrier movable about a vertical axis, a vertically arranged fuse thereon having associated vertically-spaced movable contacts, a pair of associated verticallyspaced stationary contacts, a casing inclosing said carrier, said fuse and Said contacts, and adapted to contain oil in which said parts are immersed, said casing having an opening through which said fuse is accessible only when the carrier is in inactive position, and means for moving said carrier about its axis from active to inactive position and vice versa, and for moving said fuse vertically toward and from said opening when said carrier is in inactive position.

15. A high potential oil switch comprising a fuse carrier movable about a vertical axis, a vertically arranged fuse thereon having associated vertically-spaced movable contacts, a pair of associated verticallyspaced stationary contacts, a casing inclosing said carrier, said fuse and said contacts, and adapted to contain ,oil in which said parts are immersed, said casing having in its top an opening with which the fuse registers only when the carrier is in inactive position with the movable contacts disengaged from the stationary contacts, means for oscillating said carrier from active to inactive position, and vice versa, and for moving said carrier axially toward and from said opening, and means for preventin axial movement of said carrier except w en the fuse registers with said opening.

16. A high potential oil switch comprising a fuse carrier movable about a vertical axis, a vertically arranged fuse thereon hav ing associated vertically-spaced movable contacts, a pair of associated vertically-spaced stationary contacts, a casing inclosing said carrier, said fuse and said contacts, and adapted to contain oil in which said parts are immersed, said casing having in its top an opening with which the fuse registers only when the carrier is in inactive position with the movable contacts disengaged from the stationary contacts, means for oscillating said carrier from active to inactive position, and vice versa, a movable cover adapted to close and to expose said opening, and means by which the cover is locked in closed position when the carrier is in active posi-.

tion and the carrier is locked in inactive position when the cover is in open position.

'17. A high potential oil switch comprising a fuse carrier movable about a vertical axis, a vertically arranged fuse thereon having associated vertically-spaced movable contacts, a nair of associated vertically-- spaced stationary contacts, a casing inclos ing said carrier, said fuse and said contacts, and adapted to contain oil in which said parts are immersed, said casing having in its top an opening with which the fuse registers only when the carrier is in inactive position with the movable contacts disengaged from the stationary contacts, means for oscillating said carrier from active to inactive position, and vice versa, and for moving said carrier axially toward and from said opening, means for preventing axial movement of said carrierexcept when the fuse re isters with said opening. a movable cover adapted to close and to expose said opening alternately, and means by which the cover is locked in closed position when the carrier is in active position, and the carrier is locked at the end of its axial move ment toward said opening when the cover is open.

18. A high potential oil switch comprising a casing adapted'to contain a body of oil and having a top provided with an opening, a pair of vertically-spaced stationary contacts in said casing below the level of the oil and laterally remote from said opening, a vertical fuse adapted electrically to connect said contacts, a fuse carrier on which said fuse is detachably mounted, a vertical spindle projecting into said casing and operatively connected to said carrier, and a handle for oscillating saidspindle 100 about a vertical axis to oscillate said carrier and thereby to move said fuse alternately into registration with said opening and into electrical engagement with said stationary contacts.

19. A high potential oil switch comprising a casing adapted to contain a body of oil and havmg a top provided with an opening, a pair of vertically-spaced stationary contacts in said casing below the level of 110 the oil and laterally remote from said opening, a vertical fuse adapted electrically to connect said contacts, a fuse carrier on which said fuse is detachably mounted, means for oscillating said carrier to move 115 said fuse alternately into a position where it is accessible through said opening and a position where it is in electrical contact with said stationary contacts, and a barrier movable 'coincidently with said carrier and 120 adapted and arranged to prevent access to the live currentcarrying elements when the fuse isin said accessible position.

20. A high potential oil switch comprising a casin adapted to contain a body of 125 oil and havmg a top provided with an opening, a pair of vertically-spaced stationary contactsin said casing below the level of the oil and laterally remote from said opening,

a vertical fuse adapted electrically to con- 180 nectsaid contacts, a fuse carrier on which said fuse is detachably" mounted, means for osillating said carrier to move said fuse alternately into a position where it is accessible through said'opening and a position where it is in electrical contact with said stationar contacts, and a barrier of insulating material mounted on said carrier and movable therewith to prevent access through said opening to the. live currentcarrying elements when the fuse is in said accessible position.

21. A high potential oil switch comprising a casing adapted to contain a body of oil and having a top provided with an opening, a pair of vertically-spaced stationary contacts in said casing below the level of the oil and laterally remote from said opening a vertical fuse adapted electrically to connect said contacts, a fuse carrier on which said fuse is detachably mounted,

a vertical Spindle projecting into said casing and operatively connected to said carrier, a handle for oscillating said spindle about a vertical axis to oscillate said carrier and thereby to move said fuse alternately into registration with said opening and into electrical engagement with said stationary contacts, and a barrier of insulating material mounted on said carrier and movable thereby to prevent access to the stationary contacts when the carrier is in inactive position with the fuse registering with said opening.

21 A high potential switch comprising a casing having an opening, a fuse carrier in said casing comprising a member movable about a vertical axis laterally and having a socket, a vertically arranged fuse comprising a strip of fusible material with associated contacts at the ends thereof, and an inclosing shell therefor, said shell being detachably located in said socket with the said strip substantially parallel to said axis, a pair of associated spaced contacts arranged in said casing remote from said opening to be engaged and disengaged by the fuse contacts, and means for oscillating said fuse carrier to move said fuse from its electrically active position into a position in which it is accessible for removal through said opening.

23. A high potential switch comprising a casing having an opening, a fuse carrier in said casing comprising a member movable about an axis laterally and having a socket,

I a fuse comprising a strip of fusible material with associated contacts at the ends thereof and an inclosing shell therefor, said shell being detachably located in said socket with the said strip substantially parallel to said axis, a pair of associated spaced contacts arranged in said casing remote from said opening to be engaged and disengaged by the fuse contacts, means for oscillating'said fuse carrier to move said fuse from its electrically tween said opening and said stationary contacts when said fuse is in said accessible position.

24. A high potential oil switch comprising a casing adapted to contain a body of oil,

vertically-spaced stationary contacts in said casing adapted to be immersed in said oil, said casing having in its top an opening, a fuse carrier movable about a vertical axis, a vertical fuse and movable contacts on said carrier, means for moving said carrier about said axis to and from active position, a barrier on the fuse carrier and moved thereby to a position between said opening and said stationary contacts to cut off access to said stationary contacts when the fuse carrier is in active position, a cover movable for alternately closing and exposing said opening, and means for preventing the movement of the cover to open position except when said barrier is in position to prevent access to said stationary contacts.

25. A high potential switch comprising a casing, stationary contacts in said casing, a fuse adapted electrically to connect said contacts, a fuse carrier movable about an axis to cause said fuse to be electrically connected with and disconnected from said Stationary contacts, a spindle projecting through said casing and having said carrier mounted on its inner end, said casing having an opening 10 0 disposed laterally from said spindle, an oscillatory cover adapted alternately to close and to expose said opening, and means on said spindle for locking said cover in closed position including a pin adapted to lock said 1015 cover to said casing.

26. A high potential oil switch comprising a casing adapted to contain a body of oil and having an opening, a pair of stationary contacts in the casing below the level of the oil and remote from said opening, a fuse adapted electrically to connect said contac a fuse carrier, means operatively connecte to said carrier for oscillating it about a vertical axis to move said fuse horizontally and alternately into registration with said opening and into electrical engagement with said stationary contacts.

27. A high potential oil switch comprising a casing adapted to contain a body of oil, a

pair of amociated stationary contacts in said casing below the level of the oil, a fuse adapted electrically to engage said contacts to close a circuit therethrough, a fuse carrier movable about a vertical axis to cause the 12s fuse to move horizontally into and out of electrical engagement with said contacts, and means for imparting said described movement to said carrier.

28. A high potential oil switch comprising a casing adapted to contain a body of oil, stationary contacts, each set of movable contwo or more sets of stationary contacts in tacts when engaged with a set of fixed consaid casing, with the contacts of each set tacts completing an electrical circuit between 0 disposed in different parallel horizontal them.

5 planes or zones, one or more sets of movable In testimony whereof I have afiixed my contacts movable by means exterior of said signature. casing into and out of engagement With the GRANVILLE EgPALMER. 

